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package javaapplication1;

/**
 *
 * @author user
 */
public class bai17 {
    public static void main(String[] args) {
        int[] a={1,3,5,6,7,9,10,16,18,25,36,40,70,75,100};
        
        System.out.println(BinarySearch(26, a, 0, a.length-1)+1);
    }
    
    private static int BinarySearch(int x,int[] arr,int start,int end){
        if(start>end) return -1;
        int mid=(start+end)/2;
        
        if(x==arr[mid]) return mid;
        if(x>arr[mid]) return BinarySearch(x, arr, mid+1, end);
        else return  BinarySearch(x, arr, start, mid-1);
    }
}
